As trustee



July 7, 1925. Re. 16,108

E. C. NEWCOMB INTERNAL COMBUSTION ENGINE 2 Sheets-Sheet. 1

Original Filed June 4, 1919 I I I Mmysfioa ATTORNEY July 7, 1925.

E. C. NEWGOMB INTERNAL COMBUSTION ENGINE Original. Filed June 4, 1919 I2 Shapt-Shet 2 ATTORNEY Reissued July 7; 1925.

-UNITED STATES PATENT OFFICE.

EDWARD COVERLY NEWCOMB, OFfNORTH SCITUAT-E, MASSACHUSETTS, ASSIGNOB TOTHE UNITED STATES TRUST COMPANY OF. NEW YORK, NEW YORK, N. Y., A.CORPORATION OF NEW YORK, AS TRUSTEE.

INTERNAL-COMBUSTION ENGINE.

Original No. 1,453,164, dated April 24, 1923, Serial No. 301,708, filedJune 4, 1919. Application for reissue filed April 18, 1925. Serial No.24,287.

Tu all whom it may concern:

lie it known that I, EnwAim CovnnLr NEW- 7 'comn, a citizen of theUnited States, re-

siding at North Scituate, county .of Ply-- month, and State ofMassachusetts, have invented new and useful Improvementsin'Internal-Combnstion Engines, of which the following is aspecification.

My invention relates particularly to engines of the two-cycle type andthe objects of my invention are to produce an nternal combustion engineof the two-cycle type which shall be readily controlled throughout itsentire range; to isolate partial charges of explosive mixture in closeproximity to the firing mechanism to provide means whereby the explosivemixture may expel the burnt gases without substantially comminglingtherewith; and to provide a clearance chamher in which the flamepropagation coincides with the path taken by the mixture as it entersthe compression chamber to pre vent back-firingand to accomplish theseresults without undue sacrifice of power under full throttle operation.v

The other objects of my invention will more fully appear in thefollowing spcification and claims:

I have illustrated the preferred einbodi 'ment of my invention asapplied to aneuginc of the two-cycletype in the accompanying drawings,in which Fig. 1 is a plan view of my invention. Fig. 2 is an elevationof myinvention, partly in section. Fig.

Similar numerals refer to similar parts throughout the accompanyingdrawings.

Two cycle motors as heretofore constructed have proved to be undesirableand inefficient. except when operated under sub stantially a full load.\Vhen only a partial charge of explosive mixture was admitted,

it mingled to such an extent with the burnt gases in the compressionchamber that igniignited it burned slowly and imperfectly, whichresulted in a loss of power and a marked tendency to back fire, whichrendered engines of this type unsuitable for use in automobiles andother vehicles and confined the use of two cycle engines mainly to motorboats and stationary engines where is asectional view on the line y-y ofFig. 2.

tion of the mixture wasunreliable and when their operation was almostconstantly under an approximately full load.

In my invention which is illustrated in the accompanying drawings, Ihave shown an engine 'of the two cycle type in which the difficultiesmentioned have been avoided as well as other difficulties.

In practice I have found that I can-run my engine idle with about eightpercentum of the maximum charge of the explosive mixture, whereas aboutone-third of a maximum charge is required for this purpose in two cycleengines as heretofore manufactured While maximum charges are also burnedwith excellent efficiency.

As shown in the accompanying drawings my invention has been applied to asingle cylinder engine of the two cycle type where the crank case isemployed for the compression of the explosive mixture in order that itmay be forced into the combustion chamber.

As shown in the drawings the casting 1 forms the cylinder walls, waterjacket and upper half of the crank case. I rovide exhaust ports 3, 4 and5 in the cy inder wall which are uncovered by the piston in its downwardstroke. The casting 8 forms an expansion chamber 10, into which thespent gases are exhausted through the ports 3, 4t and 5, and from whichthey pass through the orifice 10 The ca acity and conformation of theexpansion c amber 10 and of the exhaust ports are such that the burntgases readily and freely pass from all parts of the expansion chamber 10without mutual interference and the lines of flow of the burnt gasesthrough the exhaust ports and expansion chamber are such that there willbe no interference between the several streams, but, on the contrary,the exhaust gases flowing through the central port a will be ofmaterialaid to the exit of the gases through the ports 3 and 5. If desired, anexhaust pipe of the usual type may be secured to the outlet end of theexpansion chamber. The casting 8 is secured in place by studs 12 whichpass through lugs 8 cast thereon, and lugs 8 on the casting 1. Thecompression chamber which is formed in the head of the cylinder and intowhich all of the gases are compressed at the end of the compressionstroke, comprises a passage 13, which is in open communication with aspherical equalizin or rectif ing chamber 14. and extending horizonta yfrom the latter, and preferably so positioned with reference theretothat the projected centre line thereof will pass through the cent-reofsaid chamber 14, is an ignition chamber 15 which openly discharges intothe equalizing chamber 14. This horizontal chamber 15 is ofcomparatively small cross-sectional area and its total capacity isapproximately one-half the capacity of the chambers 13 and 14 and thetotal capacity of the chambers13, 14: and 15, which constitute theclearance space or compression chamber, is approximately onethird of thetotal capacity of the combustion chamber. I prefer to construct thehorizontal chamber 15 of approximately the same length as the pistonstroke, having found that a chamber of these proportions is adapted toproduce the desired results in that it will satisfactorily isolatepartial charges of explosive mixture and prevent back firing under allconditions 9f operation, including minimum and slow burning charges ofexplosive mixture. I provide a transfer pipe 16 which communicates atits lower end with the crank case in which the explosive mixture iscompressed prior to its introduction into the combustion chamber. Thethrottle valve is located in thecarburetor connected to the lower end ofthe pipe 16 and the upper end of the ipe 16 is in communication with thechem er 15 when the inlet valve 17 is lifted from its seat. I havepurposely mounted the valve17 and the mechanism 16 by which it isoperated entirely within transfer tube 16 thereby preventing allpossibility of air leaks around the stem of the valve which when valvesare struct'ion cause serious disturbances to the mixture, particularlywhen the engine is thro ttled down. The carburetor is secured to theflange 18. I

The automatic inlet valve 19 is of the usual type. The firing means 20is preferabl a jump spark plug of the usual type an is mounted attheouter end of the ignition chamber 15 in close proximity to the--.valve 17. The cylinder is provided with the usual water jacket 21.*Iilhe other parts are too well known to requireaglescriptionr In orderto obtain the nr'alximum efficiency with an engine of the two-cycletype, it is,

tu're which is not commingled with the burnt gases in the cylinder andthe burning of that portion of the mixture which is more or lessintermingled with the burnt'gases at a temperature. and pressure whichis rapidly raised as the mixture is burned.

By my construction the combustion begins at the outer end of the chamber15, and the flame propagation is through the ignition chamber 15, theequalizing chamber 14, the passage 13 and downward through the cylinderuntil it is completed, with the resultthat the mixture in closeproximity to the firing plug 20 which is not commingled with the urntgases remaining in the cylinder, is first ignited, and as the flame ispropagated through lhe ignition chamber 15,'the equalizing chamber 14and the passa e 13, the temperature and pressure are rapi ly increasedas the zone is approached in which the mixture ismore or less commingledwith burnt gases which insures the effective and rapid combustionthereof. Itiis also obvious that this construction will result in anygases which ma still be burning being isolated so far from the intakevalve 17 that all danger of back-firing will be eliminated even when amechanically operated intake valve 17 is employed, which enables me toeliminate screens and other expedients which have heretofore beennecessarfly employed to prevent back firing and which seriouslyinterfere with the free flow of mixture into the compression chamber.

The operation of my invention is as follows:

On the upward stroke of the piston the valve 19 is lifted and explosivemixture is drawn from the carbureter downinto the tube 16 and into thecrank case, if a sufficient charge is admitted. On the return stroke ofmounted in accordance wlth the usual con-' the piston the explosivemixture in the crank case and tube 16 is compressed and when the exhaustports have been uncovered by the piston and the pressure in the c linderhas fallen to approximately atmos eric pres-' sure, the valve 17'islifted and t eiexplosive mixture flows into the outer end of the chamber15 and passes forward in the direction of the arrows as shown in Fig. 2,into the equal-,

izing chamber 14, where the mixture turns and passes downwardinto thecylinder,.expellin-gthe burnt gases--through the ports 3, 4 and'5,without substantially commingling therewith; I i

.It is apparent that when the throttle valve is nearly closed and only asmall quantity of explosive mixture is admitted, thatthe mix= ture soadmitted will practically all remain in the chambers 13, 14 and 15,where it will be isolated and have but little opportunity to mingle withthe, burnt gases in the expansion chamber and that the mixture inproximity to the firing plug 20 will not be commingled to anysubstantial extentwith any "of the burnt gases. It is well known thatwith engines of .the usual type, when but a small charge of mixture isintroduced the ercentage of mixture that mingles with the urnt gases. ismuch larger than when a full char e is introduced and it is, therefore,desiralfie that when small charges are introduced the mixture shouldbeinuch richer in fuel than when a full 'charge is admitted.

With myconstruction I find that substan-- tial enrichment of the mixturewhen'small charges are admitted is not desirable because ascertained isaccounted for by the cl1ar ac-- teristics which are imparted by thecoacting the commingling of the mixture with the 'burntgases is verymuch, reduced and the mixture socommingled is burnt under highcompression.

v The high efficiency, particularly at higher loads, of the engine abovedescribed, I have passage spaces 14 and 13 to the mixture streamwh-ieh'enters the cylinder. It Wlll be I appreciated that the flowvelocity of the mixture through the ignition passage maybe different atdifferent points in the cross-section of that assage and may, for

ture charge as a whole (by the walls of theinstance, be much di erentatthe top than at the bottom, this being the effect of the ad mission ofthe mixture, under pressure,

through the poppet inletvalve 17. The im pingementrof this mixture ofnon-uniform velocity on the wall at the far side of the space marked 14and the consequent disturbanceandmixing of-what may be called the linesof flow promote an equalization of the different velocities besidesimproving the distribution of suspended liquid fuel particles in the airof the mixture. The flow lines and differing velocities being thuschanged or reorganized, direction is given to the mixpassage 13 so thatthe stream delivered into t the cylinder follows the axis of thatpassage 1 and substantiall coincides with the axis of the cylinder andoes not strike directly for the exhaust ports. Such a mixture stream,thus mixed and rectified as todirection, is

believed to possess, and experimental obserall parts of it,- se that asit expands into the stantially equal velocities on all sides or incylinder the expulsion of the residual gases of this type of which I amaware. It will of the last previous'explosion is more thorough thanwould bethe case if the stream. velocity were not uniform, that is, ifit were in. ch fasteron one side thanthe other, and the case in allprior two-cycle engines be understood that the advantage of thisdirectional control of the entering stream ,is

. diminution of the diluting effect wl 'rchithe old gases have on thefresh chargeffind that it is reflected in the engine performance by acorresponding increase in the power derived from the fuel at higherloads.

ready described.

The impingementreferred to occurs on the curved or concavepart of thespherical space 14 which is directly opposite the ignition passage andthis surface being concave is therefore inclined,-in its major part,both with reference to the general flow direction in the ignitionpassage and also with reference to thedirection of flowinto thecylinder, or to the cylinder axis; it may therefore be properly termedan inclined impingement surface, the inclination being with reference totwodifferent axes as stated. The space 14, formed bythis;impingementsurface, and the space 13 together, constitute adirecting passage, as by their coaction the laterally directed andnon-unifornr motion in the ignition passage is overcome and convertedinto theaxially directed and substantially uniform stream delivery intothe cylinder. The bulbous enlargement of the space. 14 supplements theefiectof the inclined impingement surfaceand improves thereorganlzlngand umformlzlng effect.

It produces. a slightly restricted outlet or throat through which themixture passes to the cylinder and when the passage 13 is flared orenlarged toward the cylinder the resulting shape constitutes orresemblcs a venturi, [with the ignition passage k'ppcnihg at ahighangle,-such as 90, into its entrance section. The narrow part ofthe-passage 13 is of considerably less diameter than the cylinder and issufiicicntly long to give direction to the mixture rebounding orreflected from the impingement surfaceso that the delivered streamfollows the axis of the passage with the'efi'ect above stated; it isessential that, for some part of its length at least, the directingpassage possess these relative proportions, viz, that it be lessthan thediameter of the cylinder and long enough to cause the mixture stream toproceedaxially intothe cylinder, or not toward the exhaust ports, acondition casilyjrcalizod when the whole of the clearance space is maderelatively long and of small cross area as al- It is to be understoodthat my invention'as to its broader aspects is not limited to theprecise construction herein set forth, as'

many changes may be made there-in without departing from the spirit ofmy invention and without sacrificing its chief advantages. I claim: a i

v 1. A "two cycle internal combustion engine in which the clearancespace consists of an ignition chamber of relatively smallcross sectionalarea surrounded by a cooling jacket, inlet and ignition means at the farend thereof, a flow reorganization chamber of substantially greatercross sectional area than said ignition chamber, and int o which theignition chamber dischargeaanda Venturi-like discharge outlet from theflow reorganization chamber to the cylinder and the ignitionmeans are atthe far end thereof, the major portion of the .length of said clearancespace from the inlet, toward the cylinder, being a relatively smalldiameter chamber, and a reorganizatiori" chamber .of substantiallygreater cross section than u'said major length chamber into which saidsmall diameter chamber-discharges and a discharge outlet leading to theengine cylinder through a throat of less cross section than thereorganization chamber.

.3. A two cycle internal combustion e'n g p ston, aclearance chambersurrounded-by a in which the clearance s ace 'ne of the t 81 d of 1ssurrounde by a cooling jacket an much less volume than the cylinderspace and of greater length than the piston strokeand the inlet and theignition means are at the far end thereof, the major portion of the lenh of said clearance pace being a relativey small diameter pri'iiaryignition chamber and the minor portion of said length comprising areorganization chamber of substantially greater cross section than saidprimary ignition chamber into which the latter discharges, and aVenturilike expansion portionincluding a throat of less cross sectionthan the rec nization chamber by which the reorganization chamberdischarges into the engine cylinder.

, 4. An internal combustion engine having a water jacketed clearancespace comprising a passage which is long as compared with its diameter,havin an .inlet and firing device at the remote en thereof and aVenturi-like outlet at the other end thereof, such assage comprising aplurality of portions aving approximately straight line axesintersecting at highangle, the portion of the passage at theintersecting angle being formed as a bulbous enlargement for the pur sesde-;

scribed and the axis of, theVentun-like discharge throat beingsubstantially coincident with the axis of the cylinder.

5. A two cycle combustion en 'ne in which the clearance s ace consists oa relatively long water ac eted ignition chamber, the cross sectionalarea of which is restricted but not beyond the dimensions which willpermit a full charge of mixture to enter the cylinder withoutsubstantially restricting the flow thereof, an inlet and firing means atthe remote end thereof; a flow reorgani'ihtion chamber of greater crosssectional area than said ignition chamber, and into which the ignitionchamber discharges, and a Venturi-like discharge outlet from the flowreorganization chamber. to the cylinderthrough a throat of less crosssectional area than the reorganization chamber.

' an intake port located cylinder wall adapted to be covered anduncovered by the plston, a clearance chamber comprising an ignitionchamber provided with external cooling means, an equalizing chamber anda venturi in open communication between said equalizing chamberand saldcylinder, an intake valve located at or near t.

e outer end of said ignition chamber and electrical firing mechanismoperating in the-ignition chamber and located adjacent to said intakevalve. v

7. An internal combustion engine comprising in combination a piston, apiston cylinder, exhaust ports in the cylinder wall adapted to becovered and uncovered byflie cooling jacket and consisting of anignition chamber, the axis of which 1s not coincident with the axis ofthe piston cylinder, a flow reorganization chamber into which theignition chamber discharges, and a Venturilike port through which saidflow reorganimechanism operating adjacent to said intake valve.

8. An internal combustion engine, comprising in combination a piston, apiston cylin'der, exhaust ports in the cylinder wall adapted to becovered and uncovered by the piston, a water jacketed clearance chamber,consisting of anigniti'on chamber, the axis of which is not coincidenttothe axis of the piston cylinder, a flow reorganization chamber intowhich the ign discharges, and a Venturi-hke port through which the flowreorganization chamber discharges into the-dplston cylinder, theconformation ofsai reorganization chamber and of said port being suchthat the fresh mixture will advance into the piston cylinder with asubstantiall evenfront and velocity, and in a streamavingsubstantiallythe same (:msssectional area; as the piston cylinder, means forcomposing said mixture outside of the clearance space and meansincluding a mechanicallyo erated valve for ition chamber admitting'saidcompress mixture through I said ignition chamber.

9. An internal prising in combination a pistonpafpiston cylinder,exhaust ports in t e cyl nder wall adapted to be covered and uncoveredby the piston,'a water jacketed clearance chamber consisting of anignition chamber, the axis nea'rthe outer and of.

combustion I "engine com- F chamber and a Venturi-like port, throughwhich the flow reorganization chamber discharges into the pistoncylinder, the conformation of said flow reor nizationchamber and'saidport being sum as to cause the fresh mixture to flow into the pistonchamber in a stream the cross sectional area of which is substantiallyequal to the cross sectional area of the piston cylinder, means forcompressing said. mixture outside of the clearance space and meansincluding a mechanicallyroperated valve for admitting said compressedmixture through an intake rt near the outer end'of'said i ition cham r.

10. An internal combustion engine comprising in combination a iston, apiston cylinder, exhaust ports in t e cylinder wall adapted to becovered and uncovered by the piston, a clearance chamber, consisting ofa water jacketed ignition chamber, the axis of which is not coincidentwith the axis of the piston cylinder, a water jacketed flowreorganization chamber and a Venturi-like port, through which the flowreorganization chamber discharges into the piston cylinder, theconformation of said flow reorganization chamber, and said port beingsuch as to cause the fresh mixture to flow into the piston chamber in astream the cross sectional area of which is substantially equal to thecross sectional area of the piston cylinder an-intake port near theouter end of sai ignition chamber, and firing mechanism operatingadjacent to said intake port.

11. An internal combustion engine comprising in combinatioira piston, apiston cylinder, a carburetor, means for compressing a mixture of fueland air outside of the combustion space exhaust ports in the cylinderwall adapted to be covered and uncovered by the piston, an externallycooled clearance chamber, consisting of an ignition chamber, the axis ofwhich is not coincident with the axis of the piston cylinder, a flowreorganization chamber having a Venturi-like discharge-port adapted tolaterally expand the inflowing mixture from the ignition chamber priorto its entry lnto the piston cylinder and amechanically operated valvefor admitting said compressedmixture cylinder, exhaust ports in aend ofsaid ignition chamber. 55

throughan intake port adjacent to the outer 12. An internal combustionengine comprising in combination a piston, a piston t e cylinder walladapted to be covered and. uncovered by the piston, a clearance chamber,consisting of a water. jacketed ignition chamber, the

.. axis of which is not coin ident with the axis 'of the pistoncylinder, a water jacketed flow reorganization chamber having aVenturilike discharge port adapted to laterally expand the infiowingmixture from the ignition chamber prior to its entry into the pis toncylinder, an intake -port adjacent to the.

outervend ofsaid -ignition chamber and firing ,1;

, mechanism operating adjacent to said intake ort. 1 v 13. In atwo-cycle engine, the combination of the engine cylinder provided withan exhaust outlet uncovered bythe piston and with a clearance spacesurrounded by 'a cooling means and constituted by a relatively long,transversely-disposed ignition passage, of small cross-area,communicating at an angle with a directing passage leading toithecylinder, a carburetor, means for admitting charge mixture from thecarburetor to the end of said ignition passage'most re mote from thecylinder, a spark plug adjacent said admission means, the junction ofsaid ignition. and directing passages comprising a surface receiving theimpingement of the mixture from said ignition passage, the major part ofsaid impingement surface being inclined with reference to the cylinderaxis and cooperating with said directing passage to give the mixturestream into the cylinder a direction coinciding with the direction ofthe axis of said cylinder.

14. ,In' a twp-cycle engine, the combination of the engine cylinderprovided with an exhaust outlet uncovered bythe'piston and with aclearance space surrounded by acooling means and constituted by arelatively long, transversely disposed ignition passage, of smallcross-area, communicatin at an anglewith a longitudinally-disposedirecting assage, the latter for a part of its lengt being of lessdiameter than the cylinder and being suflicientl long to cause themixture stream delivered by it to fell w the direction of the axis ofsaid passage, a car-' buretor, means for admitting variable amounts ofmixture therefrom to the end of saidi ition passage most remote from thecylindia r, a spark plug adjacent said admission means, the junction ofsaid ignition and directing passages comprising a surface receiving theimpingement of the mixture from said ignition passage, which surface isinclined to the direction of flow through said ignition passage as wellas to the direction of flow through said directing passage and coactswith the latter to give the. mixture stream the direction stated.

'15, In a two-cycle engine, the combinacarburetor and means forsupplying variable amounts of fuel mixture therefrom to said valve, thejunction of said ignition and directing passages comprising animpingement surface inclined to the directions of the flow through bothsaid pasages, and a spark plug adjacent said inlet valve. 4

16. In a two-cycle engine, the combina tion of the engine cylinderprovided with an exhaust outlet uncovered by the piston and with anexternally cooled clearance space constituted by a relatively longignition passage of small cross-area, communicating at an angle with adirecting-passage which latter passage for some part of its length is ofless diameter than the cylinderfa carburetor, means for compressing themixture'of fuel and air produced thereby, a mechanically operated inletvalve for admitting'va riable amounts of such mixture into the end ofsaid ignition passage most remote from the cylinder, the junction ofsaid ignition and directing passages comprising an impingement surfaceinclinedto the directions of flow in both said passages, and a sparkplug located in said ignition passage adjacent said inlet valve.

17. In a two-cycle engine, the combination of the enginecylinderprovided with an exhaust outlet uncovered by the piston and withan externally cooled clearance space constituted by a relatively longignition passage, of small cross-area, connecting at an angle with adirecting passage whichlatter passage opens into the cylinder, acarburetor, means for admitting variable charges of fuel mixture fromthe carburetor to the end of said ignition passage most remote from thecylinder, said directing passage being enlarged atits junction with thei ition passage and having a throat t rough which the mixture enters thecylinder, and a spark plug situated in said ignition passage at a pointreached by mum charge admission.

18. In a two-cycle engine, the ,combination of the engine cylinderprovided with an exhaust outlet uncovered by the piston and with anexternally cooled clearance space constituted by a relativelylongignition passage of small cross-area connecting at an angle with adirecting passage which latter passage opens into the cylinder, theconnection between said passages being constituted by a substantiallyspherical enlargement, a carburetor, means for admitting variablecharges of fuel mixture from the carburetor to the end of said ignitionpassage most remote from the cylinder, and aspark plug situated in saidignition passage at 'a point reached by the minimum charge admission.

the mini- 19. In a two-cycle engine, the combine-- tion of the enginecylinder provided with an exhaust outlet uncovered by the piston andwith a Water-jacketed clearance space composed of a relatively long,transversely-disposed, water-jacketed, ignition passage of smallcross-area, connecting at an angle with a, longitudinally-disposeddirecting passage whic latter passage opens into the cylinder and is fora part of its length of less diameter than the cylinder and ofsufficient length to cause the mixture stream delivered by it to followthe direction of the axis of said directing passage, the connectionbetween said passages comprising a bulbous enlargement, a carburetor, amechanically operated poppet inlet valve located at the end of saidignition passage most remote from the cylinder and adapted to admit fuelmixture'thereto from the carburetor, and a spar plug situated in saidignition passage at a point reached by the minimum charge admission.

EDWVARD COVERLY NEVVCOMB.

